package com.gdyiko.tool;


public class ShortUrlUtil {
	
	
/*	 public static void main(String[] args) {
	   
	       String sLongUrl = "https://open.weixin.qq.com/connect/oauth2/authorize?appid=wxeae24884fc77e6ff&redirect_uri=http://ymswx.pjq.gov.cn/pjWeixin/scan.jsp?v=A264_0&response_type=code&scope=snsapi_base&state=STATE#wechat_redirect" ; // 3BD768E58042156E54626860E241E999
	       String[] aResult = shortUrl (sLongUrl);
	       // 打印出结果
	       for ( int i = 0; i < aResult. length ; i++) { 
	           System. out .println( "The string [" + i + "] is " + aResult[i]);
	       } 
	    } */
	    public static String[] shortUrl(String url) {
	       // 可以自定义生成 MD5 加密字符传前的混合 KEY
	    	//String key = "nanyou" ;
	       // 要使用生成 URL 的字符
	       String[] chars = new String[] { "a" , "b" , "c" , "d" , "e" , "f" , "g" , "h" ,
	              "i" , "j" , "k" , "l" , "m" , "n" , "o" , "p" , "q" , "r" , "s" , "t" ,
	              "u" , "v" , "w" , "x" , "y" , "z" , "0" , "1" , "2" , "3" , "4" , "5" ,
	              "6" , "7" , "8" , "9" , "A" , "B" , "C" , "D" , "E" , "F" , "G" , "H" ,
	              "I" , "J" , "K" , "L" , "M" , "N" , "O" , "P" , "Q" , "R" , "S" , "T" ,
	              "U" , "V" , "W" , "X" , "Y" , "Z" 
	       };
	       // 对传入网址进行 MD5 加密
	       String sMD5EncryptResult = (Encript.md5(url));
	       String hex = sMD5EncryptResult;

	       String[] resUrl = new String[4]; 
	       //得到 4组短链接字符串  
	       for ( int i = 0; i < resUrl.length; i++) {
	           // 把加密字符按照 8 位一组 16 进制与 0x3FFFFFFF 进行位与运算
	           String sTempSubString = hex.substring(i * 8, i * 8 + 8);
	           // 这里需要使用 long 型来转换，因为 Inteper .parseInt() 只能处理 31 位 , 首位为符号位 , 如果不用 long ，则会越界
	           long lHexLong = 0x3FFFFFFF & Long.parseLong (sTempSubString, 16);
	           String outChars = "" ;
	           //循环获得每组6位的字符串
	           for ( int j = 0; j < 6; j++) {
	           // 把得到的值与 0x0000003D 进行位与运算，取得字符数组 chars 索引
	//(具体需要看chars数组的长度   以防下标溢出，注意起点为0)
	              long index = 0x0000003D & lHexLong;
	              // 把取得的字符相加
	              outChars += chars[( int ) index];
	              // 每次循环按位右移 5 位
	              lHexLong = lHexLong >> 5;
	           }
	           // 把字符串存入对应索引的输出数组
	           resUrl[i] = outChars;
	       }
	       return resUrl;
	    }
	}
